The present disclosure is directed to a camera system for vehicles for use with autonomous navigation systems (ANSs), and more particularly to a virtual pan/tilt camera system and method for use with ANSs for ground vehicles, more specifically manned ground combat vehicles.
Unmanned ground vehicles (UGVs) are valuable to the military involved in ground combat. The value of a UGV is increased when it is able to navigate autonomously as it reduces manpower that must be deployed for a given military operation. Modern ANSs for ground vehicles use machine vision to detect obstacles and navigate paths around the obstacles. Current ANSs use pan/tilt stereo cameras on the outside of the UGV so that the ANS computer can get a good view of the obstacles at close range.
ANSs used in modern unmanned ground vehicles operate using as sources of information: (1) a digital map of the terrain where the vehicle is operating that is precise to approximately a meter or better, and (2) redefined information that it deduces from the pan/tilt cameras used in the system. It also uses GPS coordinates to establish the vehicle's location. However, before the ANS directs the vehicle to begin moving, it may require a closer view of the area immediately surrounding the vehicle.
The ANS used with the present disclosure performs stereo imaging processing and autonomously navigates the ground vehicle in the same way it performs these functions when used in a pan/tilt camera system. The ANS, when used with pan/tilt cameras, receives two video data streams from a pair of pan/tilt cameras for the ANS to use to control the cameras by performing stereo image analyses. In accordance with the present disclosure, the same ANS receives two video data streams that “appear to” come from two pan/tilt cameras, when in fact they are video data streams that have been reformatted from fixed cameras.
While the present disclosure has been described by reference to specific embodiments and specific uses, it should be understood that other configurations and arrangements could be constructed, and different uses could be made, without departing from the scope of the disclosure as set forth in the following claims.
The autonomous navigation of ground vehicles is particularly difficult. To autonomously navigate over ground, detailed knowledge is required of objects down to a size that the vehicle can traverse. Therefore, ground navigation requires continuous detailed inspection of the area immediately ahead of the vehicle. For example, there may be obstacles such as trees, brush, rubble, boulders, and other objects that do not appear on the digital map. From a distance, the ANS can identify that a particular object is present, but may not be able to tell whether it is surmountable, i.e., whether the vehicle can travel over the object. To further identify and characterize such objects, the ANS causes the vehicle to navigate closer to the objects, and as it does so initiates suitable commands to the pan/tilt cameras to aim the cameras at the various nearby objects to gain better imagery of the objects. Objects that are classified as “impassable” are added to a dynamic map. The ANS selects an appropriate route, if such a route is available, and initiates commands to direct the vehicle between or around the impassable objects, and through or over the passable ones.
Pan/tilt cameras work well for an ANS and do not pose any excessive demands for most UGVs. To enable MGVs to travel while a crew is resting or disabled, and to enable the vehicles to operate unmanned when facing extreme danger, it is required that the MGV be able to operate the vehicle by remote control and navigate autonomously, such that the MGV must include an ANS. Because the current state of ANS technology requires a pan/tilt camera, a standard approach is to incorporate a pan/tilt camera into each MGV.